China's foreign exchange reserves totaled $3.029 trillion at the end of September, down $25.9 billion or 0.85 percent from August, data from the State Administration of Foreign Exchange (SAFE) showed Friday.

The country's forex reserves fell slightly for the month due to factors including the further rise in the U.S. dollar index, combined effects of exchange-rate conversion and a decline in global financial asset prices, said Wang Chunying, deputy administrator and spokesperson of SAFE.

The dollar index – which tracks the greenback versus a basket of six major peers – has surged about 17 percent for the year so far, boosted by the U.S. Federal Reserve's aggressive rate hikes.

In a briefing with reporters, Wang noted the complex and grim external environment and increased downward pressure on the global economy.

However, she reiterated that the strong resilience of the Chinese economy and solid foundation for long-term growth are conducive for the overall stability of China's forex reserves.

Elsewhere in Asia, South Korea and Japan reported sharp drops in forex reserves in September as both dug into their coffers to shore up local currencies in the face of continued dollar strength.

South Korea's forex reserves fell by nearly $20 billion in September, suffering the second-biggest monthly drop on record, the country's central bank said on Thursday.

Japan's forex reserves also shrank by a record $54 billion to $1.238 trillion for the month as the government intervened for the first time in 24 years to prop up the sharp depreciation in the yen, official data showed on Friday.

The currencies of around 90 developing countries have weakened against the dollar, and their governments have poured $379 billion of reserves to defend their currencies so far this year, UN data showed on Tuesday.